It is well known to use a combination spring and friction type vibration damper in a conventional vehicle clutch ahead of a manual transmission for the purpose of neutralizing any torsional vibrations emanating from the vehicle engine which would otherwise cause undesirable characteristics, e.g. impact loads, pulsations, noises, etc. in the transmission and driveline during operation of the vehicle.
With an automatic transmission including a hydraulic torque converter positioned between the vehicle engine and the transmission, the torsional vibrations are hydraulically dampened in the torque converter, obviating the need for a vibration damper. However, with the addition of a lock-up clutch in the torque converter to enhance the efficiency of the transmission by providing a direct connection between the engine and the transmission at higher vehicle speeds, vibrations again arise as a problem requiring a vibration damper in the lock-up clutch assembly.
Previous vibration damper assemblies have not been effective in the torque converter lock-up clutch due to the limited travel before the damper springs bottom out. A number of patents have recently issued to applicant providing an extended range of travel in the damper assembly to provide adequate damping for torsional vibrations present in the newer engine-automatic transmission combinations. The present invention provides another effective vibration damper assembly for use in manual clutches or torque converter lock-up clutch assemblies where low hysteresis is desired in a series spring coupling.